On December 30, 1989, Collier (Boyle) Landry, then 11, says he kissed his mother, Noreen Boyle, goodnight, then went to bed. It was the last time he would ever see her alive.

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Collier says he awakened to screams and loud thumps in the middle of the night. When he went looking for his mother in the morning, Collier says his father, Dr. John Boyle, told him his mom had gone on “vacation.” Collier says he soon realized that what he heard that night were actually the sounds of his mother being murdered by his father.

More than two decades after Collier’s testimony helped convict his father of murder; he says he decided to confront Boyle behind bars. That encounter became part of the Investigation Discovery documentary, “A Murder in Mansfield.”

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“I wanted to do this documentary,” Collier tells Dr. Phil during an exclusive daytime airing this Wednesday. “I wanted to go back and get the answers that I wanted from my father.”

Collier says another reason he wanted to do the documentary was that he didn’t want Noreen’s murder to be her legacy.

“I wasn’t going to let that be the final chapter.”

Check here to find out where you can watch Wednesday’s Dr. Phil.

Footage/photos provided by Investigation Discovery. “A Murder in Mansfield" premieres on Investigation Discovery and IDGO at 9 p.m. EST on Saturday, November 17, 2018.

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